The Perfect Cocktail - Barney states that he was about to sleep with his 283rd woman when Marshall interferes.

The Best Man - Barney brags that he has an 83% success rate with women (although Ted comments, "17, it's always the inverse").

In Right Place, Right Time, Marshall does the math and determines that only 1.2% of the women Barney approaches actually sleep with him, which is equal to 1 divided by 0.83.

Field Trip - Barney says that 83% of college students are in dire need of sex lessons. Coincidentally, Star Wars: Episode VI - Return of the Jedi was released in 1983, a movie which features prominently in the episode.

Good Crazy - Barney mentions his online dating success rate to be as high as 83 percent.

Now We're Even - When Barney and Ted are arguing over the points system, Barney gives Ted 83 points for slapping five with Tommy Lee.